@startuml
left to right direction
rectangle "用户登录" {
    actor user
    usecase input as "输入登录名，密码，选择人员类型（前端）"
    usecase submit as "提交登录（前端）"
    usecase check as "验证和授权（后端）"
    usecase ok as "登录成功进入系统（前端）"
    user --> input
    input --> submit
    submit -down-> check
    check -left-> ok
}

@enduml